Compactor brake

ABSTRACT

In a domestic refuse compactor for compressing refuse into an open-topped container, having: a frame: a pressure plate for contacting the refuse; and screw-type drive means carried by the frame for reciprocating the pressure plate into and out of the open-topped container, wherein the screw-type drive means includes a screw member attached in driving relationship to the pressure plate, and a driving arrangement adjacent the frame for reciprocating the screw and pressure plate, the improvement comprising a brake located between the frame and the driving arrangement to prevent locking of the driving arrangement in abutting relationship to the frame when the pressure plate is retracted to its uppermost position.

United States Patent 11 1 Hardy 1 1 COMPACTOR BRAKE [75] Inventor: Albert L. Hardy, Louisville. Ky.

[73] Assignee: General Electric Company,

Louisville. K

1221 Filed: Apr. 26, 1074 121 Appl. No.; 464.468

1 1 June 3, 1975 3.727.546 4/1973 McKinney 100/229 A 3.741.108 (1/1973 Stratman 100/229 A Primary E.\amincrBil1y .1. Wilhite [57] ABSTRACT In a domestic refuse Compactor for compressing refuse into an open-topped container. having: a frame: a pressure plate for contacting the refuse; and screwtype drive means carried by the frame for reciprocating the pressure plate into and out of the open-topped container, wherein the screw-type drive means includes a screw member attached in driving relationship to the pressure plate, and a driving arrangement adjacent the frame for reciprocating the screw and pressure plate, the improvement comprising a brake located between the frame and the drivingarrangement to prevent locking of the driving arrangement in abutting relationship to the frame when the pressure 5 Claims. 2 Drawing Figures [56] References Cited UNITED STATES PATENTS 2.658.407 11/1953 Chapman et a1 74/4248 R 2983.159 5/1961 Zeligowskv et a1. 74/4248 R t 1s re t 1ts u rmost os1t on. 3.219.154 11/1965 Schenck ct =11. 188/134 e acted O ppe p 1 3121.1 18 11/1965 Hoover 74/4248 R H l 1 2O 1 COMPACTOR BRAKE BACKGROUND OF THE INVENTION Domestic refuse compactors are in widespread use throughout the country. Such compactors normally include a cabinet having a front opening, a door for closing the opening, an open-topped container movable into and out of the cabinet, and a press or compacting mechanism mounted in the cabinet, which is movable downwardly into the open-topped container for compressing refuse therein. Many of the compactors presently on the market incorporate a scissorstype linkage arrangement for applying force to the pressure plate. Devices of this type have an inherent disadvantage, since the mechanical advantage of the linkage arrangement varies as a function of the position of the pressure plate over the length of the compression stroke.

Other compactors have been provided in which screw-type drive means are employed to generate a compacting force which is generally constant and independent of the position of the pressure plate. Such compactors suffer from a number of defects, however. One such defect is that the screw-type drive means itself, upon reversing, may tighten and jam in its uppermost position so that the motor cannot break it loose at the beginning of a subsequent compaction cycle.

The problem of the screw-type drive means jamming arises in that, under normal operation, as the pressure plate approaches its retracted or uppermost position, a limit switch shuts off the power to the motor; however, if the operator holds the start switch in the energized position past the point of operation of the limit switch, then the screw mechanism continues to retract under power and jams in its uppermost position. Correspondingly, the motor could coast after being shut off by the limit switch to cause the screw-type drive means to jam, in certain compactors.

The use of a needle thrust bearing between the screw-type drive means and the frame means of the compactor proved to be only partially effectual in solving the jamming problem. Friction was reduced between the frame means and screw-type drive means; thus, the motor was able to break loose the jammed drive means upon initiation of a subsequent compaction cycle. However, the needle thrust bearing provided no braking effect and, as a consequence, allowed the retracting screwtype drive means to engage the frame with such force that either the drive means or the power linkage from the motor to the drive means was damaged.

The present invention provides a straightforward, inexpensive, readily constructed and easily maintained means of slowing the screw-type drive means to a stop when the pressure plate reaches its uppermost position the plate on the screw means and rotatable driving and yet provides little or no resistance to the motor when the next subsequent cycle is initiated.

Attempts, such as those shown in US. Pat. Nos. 3,783,312 and 2,172,440, have been made at providing brake means for braking electric motors under no-load conditions, but such brake means are not at all suited for use in domestic refuse compactors.

SUMMARY OF THE INVENTION The present invention provides a compactor brake which is employed in screw-type drive compactors between the drive means and the frame means to arrest the upward motion of the pressure plate and provide means for driving the screw means, the improvement comprising brake means rotatably mounted in abutting engagement with the frame means and the driving means, which brake means is adapted to rotate through an arc to engage stop means mounted to said frame means to releasably arrest the rotary motion of the driving means.

The brake means of this invention has been found useful in preventing damage to the screw-type drive means ofa household refuse compactor upon return of the refuse compactor pressure plate to its uppermost or rest position.

DESCRIPTION OF THE DRAWING FIG. I is a side view, partially in section, illustrating the compacting mechanism of a household compactor employing the compactor brake of this invention, the compacting mechanism being in its uppermost position; and

FIG. 2 is a top view of the compactor brake shown in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, the compacting mechanism 20 includes as major components a pressure plate 54, screw-type drive means 56 for vertically reciprocating the pressure plate 54 and stabilizing means 58 located between plate 54 and top wall 30 for maintaining the plate 54 generally horizontal during downward movement toward and into a refuse receiving container 18.

The pressure plate 54 may be of any suitable design and conveniently includes a generally circular plate 60 sized to be received in the container 18. The plate 60 provides a pair of ribs 62 on the underside thereof to provide increased rigidity and to act as bottle breakers.

The screw-type drive means 56 for reciprocating pressure plate 54 includes a screw 64 having the lower end thereof secured in a bearing element 66 in any suitable fashion. The bearing element 66 is attached to the plate 60 by a substantially hemispherical cup 70 having an opening 72 therein for receiving the screw end. The cup 70 is attached to the pressure plate 54 in any suit able fashion, as by conventional thread fasteners 74. It will accordingly be seen that the pressure plate 54 is mounted for tilting movement relative to the screw 64 about a plurality of horizontal axes.

The upper end of the screw 64 is received in an integrally threaded sleeve 76 which is secured to a substantially spherical bearing element 78. A plurality of drive pins 80 project radially from the bearing element 78 into a like plurality ofdrive slots 82 provided by a collar 84. The collar 84 provides an internal seat 86 mating with the exterior of the bearing element 78. A retainer 88 is releasably secured to the open bottom end of the collar 84 in any suitable manner, as by a screw connection (not shown) in order to captivate the bearing element 78.

It will accordingly be seen that rotation of the collar 84 causes rotation of the sleeve 76 through the drive connection afforded by the pins 80 and the slots 82 to thereby reciprocate the screw 64. It will also be seen that the screw 64 is capable oflimited tilting movement relative to the collar 84 because of the sliding relationship of bearing 78 with internal seat 86 and the vertical extent of the slots 82.

The collar 84 provides an external upwardly facing shoulder 90 captivating a needle or roller bearing 92 against a generally horizontal flange 94 which, in turn, abuts against plate 96 of upper reaction structure 40. As will be more fully pointed out hereinafter, the plate 96 acts to transmit forces generated during compacting to top wall 30 and thence to frame 14. Flange 94 carries a tubular bearing section 98 extending through the plate 96 and ending flush with wall 30. Positioned on top of wall 30 and tubular bearing section 98 is a bearing means 100 upon which the brake means 101 of the present invention rests.

As can be more clearly seen from FIG. 2, brake means 101 includes projections 103 extending radially from the outer periphery thereof. These projections 103 are sized to extend a distance sufficient so that upon rotation of the brake means they will engage posts 105 which are rigidly supported from top wall 30. As best seen from FIG. 2, posts 105 are attached at preselected locations on plate 96 and project through top wall 30 to engage projections 103 of the brake means and allow the brake means to rotate through an angular rotation of, for example, about 70.

Resting upon brake means 101 is collar 102 which is powered from an external power source (not shown) and journalled to collar 84. It will be seen that collar 102 and collar 84 are mounted for rotation about an axis 108 defined by the sleeve 76. The collar 102 is interiorly splined to provide a driving connection with collar 84. The collar 102 is also externally splined to provide a driving connection with a large, toothed wheel (not shown) and is captivated to the collar 84 by a suitable retainer 106.

In operation, the brake mechanism of this invention functions to restrict the rotation of collar 102 as tightening occurs in the means 56 upon retraction of plate 54 to its uppermost position. Specifically, it can be seen that retracting the screw means to its uppermost position causes upper and lower reaction structures 40 and 38, respectively, to abut, which in turn causes a tightening force to be transmitted to bearing element 78 and then to collar 102 as described more fully hereinafter. The cause of such tightening can be either from the operator maintaining the start button in a depressed condition as the compacting mechanism is retracting or from the motor coasting to a final rest position. Such tightening heretofore caused retainer 106 to break apart or the top of collar 84 to break off. However, the addition of brake means 101 prevents this from happening.

As noted above, the brake means 101 functions to restrict the rotation of collar 102 and thus restrain the upward motion of circular plate 60 and lower reaction structure 38. Such restriction prevents the means 56 from jamming when the plate and reaction structure are in their uppermost position as follows: When lower reaction structure 38 abuts upper reaction structure 40, any further rotation of sleeve 76 tends to pull the reaction structures more closely together. Screw 64 pulls on hemispherical cup and, in turn, sleeve 76 pulls downwardly on spherical bearing element 78 which, in turn, pulls downwardly on retainer 88 and thus on collar 84. Such downward force puts pressure on retainer 106.

As explained earlier, if the lower reaction structure abuts the upper reaction structure under power, the force transmitted to retainer 106 may be sufficient to cause it to break. In the alternative, the upper portion of collar 84 supporting retainer 106 may break off. To avoid such a consequence, brake means 101 is inserted on top of bearing means in abutting relationship to collar 102. Under the circumstances described above, when a downward thrust is exerted through collar 84, collar 102, which is rotating, comes into forceful engagement with brake means 101, thus exposing brake means 101 to a rotating force. As this happens, brake means 101 is more forcefully compressed between bearing means 100 and collar 102 until it begins to rotate with collar 102. Brake means 101 rotates through an angle of, for example, about 70 until the leading edges 107 of projections 103 come into contact with posts 105, attached to plate 96 and projecting through top wall 30, at Which time break means 101 is prevented from further rotation. The tightening between collar 102 and bearing means 100 is ever increasing; thus, the frictional forces between collar 102 and brake means 101 quickly become sufficient in magnitude to stop the rotation of collar 102. As can be seen, the braking function of the brake means 101 is a gradually increasing type of braking effect which prevents an abrupt stopping of the moving parts of means 56. In addition, it is easily recognizable that to begin a subsequent compaction cycle, collar 102 will be rotating in the opposite direction. Thus, brake means 101 with which collar 102 is now firmly engaged is free to rotate through an arc of, for example, 70 Upon rotation through such a 70 arc, the tightening force between collar 102 and brake means 101 will have been dimin ished to such an extent that when the following edges 109 of projections 103 abut respective posts 105, collar 102 will be easily rotatable being only in light frictional contact with brake means 101. Thus, brake means 101 provides braking of the means 56 and easy release or break loose upon initiation of a subsequent compaction cycle.

It should be noted that, although brake means 101 has been shown and described as having three projections abutting corresponding posts, other similar brake means could be devised. For example, a suitable brake means having only one projection abutting only one post could be employed, under certain circumstances; whereupon, the brake means would rotate through an arc of less than about 360 in preforming the braking function. Similarly, a brake means having a plurality of projections and posts could be employed. In such an event, the rotation of the brake means may be through an arc of 30 or less in performing the braking function. Also, the brake means need not be of any specific shape as long as provision is made for it to releasably engage stop means to effect braking.

It should also be noted that if a needle bearing is selected as bearing means 100, then it can be seen that brake means 101, which is in contact therewith on its underside, would be even more easily broken loose upon initiation ofa subsequent compaction cycle. Such a bearing itself also minimizes the frictional forces which the motor must overcome to break loose collar 102 and begin the compaction cycle.

Another feature of the compactor described herein is illustrated in FIG. 1 wherein the bottom of the sleeve 76 is disposed well below the top wall 30 at a location where the pressure plate 54 clears the container 18 upon the termination of the upward movement of the screw 64. Thus, the length of the stroke of the screw 64 is measured from adjacent the bottom of the sleeve 76 rather than from the top wall 30. Since about half of the screw 64 is below the top wall 30 of the compactor in the uppermost position of the screw 64, it is readily apparent that the overall height of the compactor has been substantially reduced. It will be apparent that the compactor may be placed under a conventional sink since the screw 64 only projects upwardly above the top of the compactor a maximum of about V2 of its overall length.

It will be noted that the screw is directly connected to the pressure plate 54 rather than being connected thereto through a linkage mechanism. Thus, the resistance to movement sensed by the screw 64 is the resistance due to compacting refuse, rather than a mechanical disadvantage appearing in a linkage arrangement. Accordingly, the full output of the motor (not shown) with the exception of any friction losses, is delivered to the pressure plate 54 at all vertical positions of the screw 64. Thus, the compacting force delivered by the compacting means 20 is relatively constant and independent of the vertical position of the pressure plate 54. It is, of course, fully apparent that the means 58 for maintaining the pressure plate 54 horizontal during downward movement thereof is wholly independent of the screw 64 and sleeve 76.

Having thus described the invention, what is claimed 1. In a household refuse compactor of the type having: frame means providing a compacting chamber including an access opening thereinto; a door mounted for movement between positions opening and closing the access opening; means for supporting an opentopped container in the chamber; a pressure plate for movement into and out of the container for compress ing refuse therein; screw-type drive means supported by the frame means for vertically reciprocating the pressure plate, the screw-type drive means including screw means; means mounting the plate on the screw means; and rotatable driving means for driving the screw means; the improvement comprising brake means rotatably mounted in abutting engagement with said frame means and said driving means, said brake means being adapted to rotate through an arc in response to a tightening force between said frame means and said driving means to engage stop means, thereby releasably arresting the rotary motion of said driving means. 7

2. The refuse compactor of claim 1 wherein the rotation of said brake means is limited to an angular rotation of less than 360.

3. The refuse compactor of claim 1 wherein said brake means is a rotatable flat disc and said frame means includes bearing means in contact with said brake means.

4. The refuse compactor of claim 3 wherein said brake means includes tab portions radially extending from said flat disc to engage said stop means.

5. The refuse compactor of claim 4 wherein said stop means includes a plurality of posts rotatably engageable by said tab portions. 

1. In a household refuse compactor of the type having: frame means providing a compacting chamber including an access opening thereinto; a door mounted for movement between positions opening and closing the access opening; means for supporting an open-topped container in the chamber; a pressure plate for movement into and out of the container for compressing refuse therein; screw-type drive means supported by the frame means for vertically reciprocating the pressure plate, the screw-type drive means including screw means; means mounting the plate on the screw means; and rotatable driving means for driving the screw means; the improvement comprising brake means rotatably mounted in abutting engagement with said frame means and said driving means, said brake means being adapted to rotate through an arc in response to a tightening force between said frame means and said driving means to engage stop means, thereby releasably arresting the rotary motion of said driving means.
 1. In a household refuse compactor of the type having: frame means providing a compacting chamber including an access opening thereinto; a door mounted for movement between positions opening and closing the access opening; means for supporting an opentopped container in the chamber; a pressure plate for movement into and out of the container for compressing refuse therein; screw-type drive means supported by the frame means for vertically reciprocating the pressure plate, the screw-type drive means including screw means; means mounting the plate on the screw means; and rotatable driving means for driving the screw means; the improvement comprising brake means rotatably mounted in abutting engagement with said frame means and said driving means, said brake means being adapted to rotate through an arc in response to a tightening force between said frame means and said driving means to engage stop means, thereby releasably arresting the rotary motion of said driving means.
 2. The refuse compactor of claim 1 wherein the rotation of said brake means is limited to an angular rotation of less than 360*.
 3. The refuse compactor of claim 1 wherein said brake means is a rotatable flat disc and said frame means includes bearing means in contact with said brake means.
 4. The refuse compactor of claim 3 wherein said brake means includes tab portions radially extending from said flat disc to engage said stop means. 